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IDLffShape::AddAttribute

Syntax | Arguments | Keywords | Examples | Version History

The IDLffShape::AddAttribute method adds an attribute definition to a Shapefile. Adding the attribute definition is required before adding the actual attribute data to a file. For more information on attributes, see Attributes.


Note
You can only define new attributes to Shapefiles that do not have any existing values in any attributes.

Syntax

Obj->[IDLffShape::]AddAttribute, Name, Type, Width [, PRECISION=integer]

Arguments

Name

Set to a string that contains the attribute name. Name values are limited to 11 characters. Arguments longer than 11 characters will be truncated.

Type

Set to the IDL type code that corresponds to the data type that will be stored in the attribute. The valid types are:

3
Longword integer
5
Double-precision floating-point
7
String

Width

Set to the user-defined width of the field for the data value of the attribute. The following table describes the possible values depending on the defined Type:

Longword Integer
Establishes the number of digits of the largest number that can be represented
Double-precision floating-point
Establishes the total number of digits, including the decimal point and the number of positions after the decimal point (see the PRECISION keyword)
String
Establishes the maximum length of the string that can be stored

Keywords

PRECISION

Set this keyword to the number of positions to be included after the decimal point. The default is 8. This keyword is only valid for fields defined as double-precision floating-point.

Examples

For an example of AddAttribute, see Creating New Shapefiles.


Note
If cities.shp already contains data in an attribute for any of the entities defined in the file, this operation will fail.

Version History

5.4
Introduced

  IDL Online Help (March 06, 2007)